Combined camera and exposure meter



Sept. 16, 1941. 1.. LEITZ ETAL COMBINED CAMERA AND EXPOSURE METERINVENTORS Ludwig Leitz & HBlHPlBh Broschke Filed Dec. 12, 1940 PatentedSept. 16, i941 UNITED STATES PATENT OFFICE ""W'COMBINEDCAMEBA-ANDIXPOBUIBIETII Ludwig leitaandlleinrichltcecmwetalar,

Application December is, me, Serial s... 'lnqermanylassaaryldsie a cum.(cl. ss-m This invention relates to improvements infthe mechanisms usedin photographic apparatus combined with exposure meters for selectivelydistributing the exposure value indicated by the meter upon the exposurecontrolling elements of a photographic camera. In some cameras "theseelements be spaced some distance apart and such a distributing mechanismis apt to become rather complicated. In a motion picture the mechanismbecomesvery complicated be:- cause thetime adjustment of theshutter mustbe divided between the picture irequency regulater and the shuttersector regulator. 11 ad- 1 justment with respect to the film sensitivityis also included there are altogether four factors The object 0! thisinvention is to provide an improved mechanism for coupling or connectingthe exposure controlling elements of a camera,

particularly. a motion picture camera, with the exposure indicatingmeans of a photoelectric exposure meter whereby the adjustment 0! theseelements to accord with the indicated exposure value may be done in avery simple manner. The invention is illustrated inthe accompanyingdrawing in which Fig. 1 is a perspective view a! a motion picture cameraequipped with a coupling or connecting mechanism according to theinvention. I'ig. 2'is a diagrammatic perspective view of and associatedparts.

In the drawing the camera I is provided with an exposure metercomprising a photoelectric cell 2 which receives reflected light from amir- 8. The cell actuates a galvanometer including a magnate, a-rotor land a pointer I. A

"transparent disk I is mounted on. a rotatable ahait II. The diskcarriesexposure indicating marks 0, and these. latter and the pointer areobserved in an ocular (not shown) through a prism ,I. The camera has anobjective II; a shutter. il anda picture'irequency regulator l.Theseelementsmaybeoi'an usualtypea'nd are indicated only in outline.Their general operation and function are well known in the art. Theobjective has a diaphragm 2: adjustable as usual by a rotatable ring 33which has a cam 2|.

The latter is engaged by a bell crank 2| which in turn carries a pulleyit. As the diaphragm is adjusted by rotating the cam ring, thepuliey llmoves up or down. The picture frequency regulator may be adjusted bymoving a shaft ll up or down, the operation being obvious .irom

the drawing. The shaft is moved by'a knob ii isbiltisslackenedthedis'klmovesclockwise. to be considered in order toobtain correct ex- I posure adiustment.

2s 21 and a picture i The operation is as iollows: when the camera coiaykn ob u.

shattll carries a pulley ii to which 7 a -rband, I3 is attached'undertension by a spring it. The therefore iend sto rotate the disk anpulleyciockwise lung. 2. To the pulley ll d7. io'isfjlso a transmissi'on belt I! which daepulie'ysilandllontheshaits m; mun" the belt islengthened it unwinds from the pulley disk 8 anticlockwise. The

piste-ct the camera and are held there by Irishim sensitivity scal 2],ashutter opening .scale uency scale II,

. is loaded with iilm the sensitivity adjuster 23 is moved tov theproper position indicated on the sensitivity scile II andthebelt' l2will be corre- =0 either shortened or lengthened.

Thereafter the photographer may decide upon a I certain opening, forinstance, and rotate cam ring I! to elect such opening.

tly, the pulley indicatlng such ad- Consequen I Niustment o!thedianhragmpwill be raised or loweredaccordinglyandthebeltvariedinitslengthwithrespectto thepuliey ll. the photographer may decide to operatewith a certainpictureirequencyandtheirequencyin- 40 dicator Iliaadjusted accordingly opposite a selected index on'the scale 28. Thecamera is .thenaiinedattheobjectandthepointerewiibdeflect and assume anexposure indicating position. It will thus beiound that because of thelengthwise movements, of the belt I! resulting ircmtheadjuatimoperations oi theelements it, ll'and llasaioresaidthedisktwilihavebeenrotated until either one at the'marks I registers withthc'pointeriornone oithe marks 0 registsrswiththepointe'r. Intheflrstcasenoiurtheradjustment is necessary. In the second cassthe shutter adjustmentindicator II will be movedupordownsosstomovethebelt I2 lengthwise tocause rotation of the disk 8 until on the front of the camera. Theshutter sector 55" that mark I which is nearest the :pointer is othermeans. not shown. The slots ior' brought into register therewith. Thecamera is a now adjusted for an exposure which is indicated by theposition of the pointer 6;

The correct adjustment of the exposure controlling elements may ofcourse also be done by selecting apicture frequency and a shutteropening and thereafter adjust the diaphragm to cause the final rotationor movement of the disk 8. Or a shutter opening and a diaphragm openingmaybe predetermined and the frequency regulator moved to cause the finalrotation of the disk 8. The feature of the invention is that byoperatively interconnecting the four factor elements 23, 22, i6 and illwith the exposure'indicator disk 8 by means of a single operativeelement, .namely the belt l2, exposure adjustment is eifected by thesimple expedient of moving the belt lengthwise in either direction inaccordance with-the adjustment of any one or all of the factor elements.In addition, by moving the plate 28 up or down, the frequency indicatorand the shutter sector indicator may be adjusted together withoutchanging the exposure time and without changing their mutual adjustment.e We claim: I

1. Iri a combined photographic camera and exposure meter, said camerahaving a film sensiltivity adjuster, a diaphragm and diaphragm adjuster,a shutter and shutter adjuster and means for holding said adjusters intheir adjusted positions; said meter having a photoelectrically actuatedexposure indicating pointer; a rotatable disk and pulley mounted inoptically operative relation to said pointer, said disk having exposureindicating marks adapted to be moved into registry with said pointer byrotation of said disk and pulley, a transmission belt having one endconnected to said sensitivity adjuster and the other end connected tosaid pulley, the free run of said belt operatively engaging said otheradjusters, spring actuated means for rotating said disk and pulley inone direction and means for moving said adjusters tovary the free run ofsaid belt in accordancewith such movements to cause rotation of the diskand pulley in the same or opposite direction whereby to move one of saiddisk marks into register with said pointer to indicate correct exposureadjustment of said diaphragm and shutter.

2. In a combined photographic camera and exposure meter, said camerahaving a fllm sensitivity adjuster, a diaphragm and diaphragm adjuster,a shutter and shutter adjuster and means for holding said'adjusters intheir adjusted positions; said meter having a photoelectrically actuatedpointer for indicating exposure; a rotatable disk and pulley mounted inoptically operative relation to said pointer, said disk hav- -exposureindicating marks adapted to be moved into registry with said pointer byrotation of said disk and pulley, a single flexible member having oneend connected to one of said adjusters and the other and connected tosaid pulley with the intermediate portion of said flexible member inoperative engagement with all the other adjusters.,spring actuatedmeansconnected to said pulley constantly tending to rotate the same andsaid disk in one direction and means for individually moving saidadjusters to actuate said flexible member .in accordance with suchmovements to cause rotation of said diskand' pulley in the same-oropposite direction whereby to move one of said disk marks into registrywith said pointer-to indicate correct exposure adjust-- ment ofsaid-diaphragm and shutter 3. In a photographic apparatus according toclaim 2 in which said camera is a motion picture camera having also apicture frequency regulator-and adjuster therefor, the said intermediateportion of said flexible member also engaging saidfrequencyadjusten'said registry position of said disk mark with saidpointer also indicating cor-. rect exposure adjustment of said picturefrequency regulator.

10 4. In a, combined motion picture camera and exposure meter, saidcamera having a film sensitivity adjuster,'a diaphragm and diaphragmadjuster, a shutter and shutter adjuster, a picture frequency regulatorand adjuster therefor and means for holding said adjusters in theiradjusted positions; said meter having a photoelectrically actuatedexposure indicating pointer; a

' rotatable disk and pulley mounted in optically operative relation tosaid pointer, said disk having exposure indicating marks adapted to bemoved into registry with said pointer by rotation of said disk andpulley, a transmission'belt having one end connected to said sensitivityadjuster and the other end connected to said pulley,

' the free runof 'sald belt operatively engaging said other adjusters,spring actuated means for rotating said disk and pulley in one directionand means for moving said adjusters to change the free run of said beltin accordance with such movements to cause rotation of said disk andpulley in the same or opposite direction whereby to move one of saiddisk marks into registry with said pointer to indicate correct exposureadjustment of said adjusters, means for simultaneously additionallyadjusting the'shutter adjuster and the frequency adjuster whilemaintaining the registry position of said mark and pointen.

5. In a combined motion picture camera and exposure meter, the latterhaving a photoelec- 40 trlcally actuated exposure indicating pointer,said camera having a film sensitivity adjuster, a shutter and.shutteradjuster, a picture frequency regulator and adjuster therefor,scales on said camera indicating the positions of said adjusters, 5 meanfor holding said adjusters in their adjusted positions, and a variablediaphragmand a cam ring for adjusting the same; a rotatable disk andpulley mounted in optically operative relation to said pointer, saiddisk having exposure indicating marks adapted to be moved into registrywith said pointer by rotation of said disk I and pulley, a transmissionbelt having its one and connected to saidsensitivity adjuster and itsother end connected to said pulley, the free run 550i said beltoperatively engaging all of said ad-' justers along said belt, springactuated means connected to said pulley and constantly urging rotationthereof in one direction, means for movsaid adjusters selectively fromsaid positions to other selected positions .to lengthwise change thefree run 'of said belt in accordance with such movements to causerotation of said disk and pulley in the same or opposite direction, amem-,-

7 the free run of said belt resulting in moving one of said disk marksinto registry ,with said pointer whereby to indicate correct exposureadjustment of theexposure controlling elements of said 6, In a cameraand exposure meter mechfor determining the correct exposure position ofsaid elements comprising in combination a light sensitive cell with apointer actuated thereby, a rotatable member having exposure indicatingmarks in optically operative relation to said pointregistry withsaidpointerby such adjustments or said exposure controlling elements aswi1l givecorrect exposure by apportioning the full light value indicatedby the deflection of the pointer in selected proportions between saidexposure contrically actuated exposureindicating pointer, said camera'having a plurality of exposure controlling elements; mechanism forselectively distributing said indicated exposure value upon saidelements,

said mechanism comprising a ,rotatable disk.

mounted in optically operative relation to said pointer, saiddisk havingexposure indicating marks adapted to be moved into registry with saidpointer by rotation of said disk, a transmission belt constantlyoperatively connected to said disk and to all of said exposurecontrolling elements and means for independently and selectivelyaddusting any one of said elements to actuate said belt to causerotation of said disk to an extent directlyproportional to theadjustment of said element. 1

9. In a combined photographic camera and exposure meter according toclaim 8 including means for adjusting all of said exposure controllingelements to actuate said belt to cause rotation of said diskto move oneof said marks into registry with said pointer to indicate correctexposure adjustments of said elements and means for thereaftersimultaneously adjusting some of said elements with relation to saidbelt while maintaining the registry position of said mark andpointLUDWIG LEII'Z. HEINRICH BRDSCI'IKE.

